Publication Citation: Testing the Performance of Hydrogen Sensors

NIST Authors in Bold

Author(s):

Nathan D. Marsh;Thomas G. Cleary;

Title:

Testing the Performance of Hydrogen Sensors

Published:

September 08, 2009

Abstract:

The acceptance of hydrogen as a widely-available energy source will depend to some extent on the perceived and actual safe dispensing and storage of hydrogen by the general public. Reliable detection of an accidental hydrogen gas release and mitigation of the hazard through designed safety systems is a key component of hydrogen powered systems in commercial, residential, and transportation uses. In anticipation of this emerging market, inexpensive hydrogen gas sensors based on a range of sensing technologies are becoming increasingly available. We have developed a new bench-scale test apparatus for hydrogen sensor performance, the Hydrogen Detector Environment Evaluator (HyDEE), based on our previous experience with hydrogen sensors in a small flow cell and in the Fire Emulator / Detector Evaluator. In particular, we have found that dynamic changes are relevant to hydrogen sensor performance, as they affect both response rate of the sensor and are also necessary to return the sensor environment to its baseline state. The ability to induce dynamic changes is most easily accomplished with a flow system similar to a small wind tunnel. In this system, we can expose sensors to hydrogen and other gases (particularly hydrocarbons, which many hydrogen sensors are also sensitive to) as well as humidity and changes in temperature. Improvements over the previous exploratory tests include substantially reduced volume allowing higher gas concentrations, and the ability to cool the system as well as heat it, in order to achieve a wider dynamic range in temperature and to more accurately simulate the environments to which sensors may be exposed in the real world.